Hey there folks.

I recently did a full body swap on my 1985 f350 crew cab. Both trucks ran just fine prior to the swap.

well after I swapped the body, wiring, and fuel system onto my donor chassis I can't seem to get the truck to run for more than a minute before it sputtered and bogs down then dies. It wont start again until a few minutes has passed. When it runs it seems to run fine but starting causes it to backfire a little bit. At first I thought it was getting to much gas and floodingI put a ppressure regulator on it with no luck. I also checked the fuel lines for leaks with no luck. I dont understand what it can be and im at my wits end.

Im hoping the kind folks here can help me out

The donor truck (chassis)
1985 f350 crew 4x4 460 auto. This truck had a mechanical fuel pump

The donor truck (body, wiring, fuel systems)
1984 f350 crew 4x2 460 auto. This truck had a electronic pump

Both truck were carburated

Thanks for the help,

Sam

 

When it bogs and quits, leave the engine off and go around and take the aircleaner off and look down the carb with a flashlight and push the throttle wide open with your hand. You should see two strong streams of fuel pour into the engine. If you get little or nothing, you have a fuel problem.

If you have a fuel problem, you need to make sure you are getting power to the fuel pump inside the tank. This system is a little bit complicated. You would think it all would transfer over if you used all the components and the wiring, but something may have been missed.

You should have a odd wire over at the starter solenoid(relay) on the inner fender. You will have the large battery and starter wires, and then the small red/blue stripe wire for cranking, and then another small wire(might be violet or purple) going to another small terminal. This terminal gets 12v when cranking, and powers the pumps directly. If you want to do a quick test, take this wire off and hook it temp to the battery +. The pump should run and the engine should keep running.

The rest of the system that powers the pumps has a relay, a oil pressure switch that powers the relay. I think the relay is over near the power brake booster area.